Our general aim is to continue to study the details of the crystal structure and solution chemistry of the interactions of metal complexes and ions with nucleic acids, nucleic acid constituents and nucleotides as they are involved in nature or can be applied to probe the stucture, function and synthesis of these biomolecules. Some of our principal interests are to study and evaluate: general metal binding selectivity to the nucleic acid basis; the role of secondary metal binding sites on the nucleic acid bases; the influence of metal coordination on base pairing and base stacking; mixed purine-pyrimidine metal complexes; metal complexes of dinucleoside monophosphates as models for labeled mini-helices; metal regulated winding and unwinding of coiled nucleic acids; Cr(III)-nucleotide and other related complexes useful as probes of enzymes and nucleic acid biosynthesis; anion interactions with neutral and protonated nucleic acid derivative osmium tetraoxide/ligand, Pt(II) derivatization of nucleic acid monomers and polymers; organomercury derivatives of nucleic acid monomers and polymers which serve as probes of enzyme structure and function; possible intercalative interactions of aromatic chelate Cu(II) complexes with nucleic acid polymers; purification, separation and base sequencing of nucleic acids by metal complexes. Our principal approach to these problems involves an extensive cross-correlation of information obtained from synthetic, solution, 1H, 13C and 31P NMR, and optical spectroscopic, and X-ray-diffraction experiments. We believe that only by such an extensive cross-correlation of information can one achieve significant solutions to the varied and complex problems outlined above.